The Anatomic Study on Replacement of Artificial Atlanto-odontoid Joint through Transoral Approach

In order to provide anatomical basis for transoral approach （TOA） in dealing with the ventro lesions of craniocervical junction, and the design and application of artificial atlanto-odontoid joint, microsurgical dissecting was performed on 8 fresh craniocervical specimens layer by layer through transoropharyngeal approach. The stratification of posterior pharyngeal wall, course of vertebral artery, adjacent relationship of atlas and axis and correlative anatomical parameters of replacement of artificial atlanto-odontoid joint were observed. Besides, 32 sets of atlanto-axial joint in adults＇ fresh bony specimens were measured with a digital caliper and a goniometer, including the width of bony window of anterior arch of atlas, the .width of bony window of axis vertebra, the distance between superior and inferior two atlas screw inserting points, the distance between two axis screw inserting points etc. It was found that the width of atlas and axis which could be exposed were 40.2±3.5 mm and 39.3±3.7 mm respectively. The width and height of posterior pharyngeal wall which could be exposed were 40.1±5.2 mm and 50.2±4.6 mm respectively. The distance between superior and inferior two atlas screw inserting points was 28.0±2.9 mm and 24.0±3.5 mm respectively, and the distance of bilateral axis screw inserting points was 18.0±1.2 mm. The operative exposure position through TOA ranged from inferior part of the clivus to the superior part of the C3 vertebral body. Posterior pharyngeal wall consisted of 5 layers and two interspaces： mucosa, submucosa, superficial muscular layer, anterior fascia of vertebrae, anterior muscular layer of vertebrae and posterior interspace of pharynx, anterior interspace of vertebrae. This study revealed that it had the advantages of short operative distance, good exposure and sufficient decompression in dealing with the ventro lesions from the upper cervical to the lower clivus through the TOA. The replacement of artificial atlanto-odontoid joint is suitable and feasible. The design of artificial atlanto-odontoid joint should be based on the above data.

Thornwaldt Cyst: Case Report

Thornwaldt cyst is benign, mucosal congenital cyst which is located in upper nasopharynx. It developed in nasopharyngeal bursa if opening of bursa is occluded due to infection or inflammation. It is rare congenital cyst present in nasopharyngeal bursa. Its incidence is 3% in adults [1]. The usual age of presentation is 2nd and 3rd decade [1]. It is usually asymptomatic and incidental finding on MRI but it can present as nasal obstruction, post nasal drip, halitosis, occipital headache, foreign body sensation in throat [1] [2]. Here we are presenting a case report of 23 years old male presented with foreign body sensation in throat since 5 months. On oral and nasal endoscopic examination cystic mass in nasopharynx seen, bulging in oropharynx. MRI shows cystic mass arising from left side of nasopharynx popping up in oropharynx. Cyst then excised with diode laser with both endonasal and transoral approach with zero degree rigid endoscope. Histopathology confirmed the cyst as thornwaldt cyst.

Imaging and choosing the right patients for transoral endoscopic parathyroidectomy vestibular approach

Advances in imaging for preoperative localization have propelled the widespread adoption of minimally invasive/focused parathyroidectomy in primary hyperparathyroidism.Though it is performed through a relatively small incision,studies have shown that the presence of a neck scar increases attentional bias towards the neck resulting in compromised quality of life.Transoral endoscopic parathyroidectomy vestibular approach(TOEPVA)eliminates a neck scar.While indications for TOEPVA are the same as that of minimally invasive open parathyroidectomy,confident preoperative localization of the parathyroid with a surgeon performed ultrasound along with concordant localization with SPECT CT is an essential prerequisite before offering patients this approach for parathyroidectomy.Early data has demonstrated the feasibility and safety of this approach.

The pros and cons of additional axillary arm for transoral robotic thyroidectomy

Background:Transoral vestibular approach thyroidectomy using robotic system has advantages with articulating instrumentation.Transoral robotic thyroidectomy(TORT)can be done either using just two robot arms for instruments and an extra one for the endoscopic camera,or using three robot arms for instruments(third arm through axila)and an additional arm for the camera.Pros of additional axillary arm for TORT:The 4th arm through an additional axillary port is mainly responsible for a counter-traction of strap muscles and thyroid tissue.The additional axillary port tract is also an excellent passage for the specimen removal with lower risk of disruption or fragmentation.Ultimately,these merits from the additional axillary arm allows TORT to be performed safely in a wide range of patient groups.Cons of additional axillary arm for TORT:One of the issue with the additional axillary arm in TORT is that it leaves a cutaneous scar.Another issue to consider is the cost.In some places,robotic surgery operation fee varies with the number of arms used during the operation.Retraction of strap muscles through subcutaneous stitches applied after establishing the working space may make up for the lack of counter-traction.Conclusion:TORT can be done safely with or without the transaxillary arm and surgeon may consider pros and cons based on multiple factors.